Improvement in treadle-powers



A. H. STEVENS.

TREADLE-POWER.

Patented Jan. 11,1876.

No.17Z,197.

Wz'fnesses N PETERS. PKOTG-LITHOGRAPHER, WASWNGTOH, D C

UNITED STATES PATENT OFFICE.

ALONZO H. STEVENS, OF CLINTON, CONNECTICUT, ASSIGNOR ONE-HALF HIS RIGHTTO MELVILLE M. JOHNSTON, OF NEW YORK CITY.

IMPROVEMENT IN TREADLE-PO WERS.

Specification forming part of Letters Patent No. 179,197, dated January11,1376 application filed o September 16, 1875 of Clinton, in the countyof Middlesex and State of Connecticut, have invented certain new anduseful Improvements in Treadle-Power; and I do hereby declare that thefollowing is a full, clear, and exact description thereof, which willenable others skilled in the art to which it per tains to make and usethe same, reference being had to the accompanying drawing, and to theletters of reference marked thereon, which form a part of thisspecification.

This invention has been designed with special reference todentalengines,althoughitisdoubtless susceptible of more generalapplication.

The particular object I have had in view is to allow the dental engineto be placed in any position desired-relatively to the operator and thepatient-as,for instance, on the side of the chair opposite to that onwhich the operator stands-and yet be fully under the control of theoperator; or, incase of a suspension-engine, to allow that to be soplaced as to keep the cords by which it is operated out of the way ofthe operator and the patient as well.

The main element of the mechanism I employ is a shaft having a crank ateach end, one connected with the pitman of the drivingwheel of theengine, the other with the treadle by which the shaft is rocked. One endof the shaft is supported ina bearing attached to the engine; andthishearing I prefer to swivel, so that it may turn upon a vertical axis.The other end of the shaft has its bearing in a movable stand or base. Iprefer to give flexibility to the shaft, and for this purpose, as apreferred mode, 1 make it in sections-usually two--united by a universaljoint.

The accompanying drawing represents an apparatus embodying my invention.

The figure is a perspective view of said apparatus.

Ais the rock-shaft hereinbefore referred to. It is supported at one endin a bearing, a, that is swiveled to turn on a vertical axis in abracket, B, clamped or otherwise attached to'the standard or frame I) ofthe engine. I have represented only so much of the engine as is needed'to illustrate my invention in its application thereto. 0 is the .fly ordriving wheel of the engine, provided with a crank-pin, c, to which isconnected one end of the pitman D, which is connected at the other endto a crank-arm, d, on the end of shaft A. The shaft at its other endtakes a bearing, 6, in a stand,E, that also supports the crank F, towhich the treadle G is connected. The stand or treadle-support E ismovable, occupying no fixed position with relation to the engine, butcapable of being moved from point to point, as the necessities of thecase may demand. The shaft is divided into two sections, united by agimbal-joint, g, or an equivalent joint, which will permit the onesection to be at an angle with the other, while both rock or rotate inunison.

Under this arrangementit will be perceived that the whole apparatus maybe moved on the bearing a as a pivot, While, at the same time, thetreadle portion can be set at an angle to that portion of the shaftattached directly to the engine. This arrangement permits of all freedomof movement necessary for the purposes of my invention.

I also unite the foot-piece or treadle-proper G with the crank F bymeans of a swiveled eye or connection, f, which permits the treadle tobe turned to one side or other of the crank, as desired, and to beplaced at any desired angle thereto, as indicated by dotted lines in thedrawing.

The shaft may be of any desired length. It will, perhaps, be founddesirable to form in it, at one point, a telescopic joint, or tootherwise unite its sections, so that'the one may slide on the other, inorder to increase or decrease at pleasure the working length of theshaft. The joint for this purpose will, of course, beformed at someother point than that occupiedby the universal joint g.

I would remark that, in practice, the crank dis longer than the crankc-that is to say, is set further from its center of motionso that a mererocking motion of the shaft will effect the rotation of the fly-wheel.Any of the usual arrangements may be employed for the purpose ofthrowing the fly-wheel past the deadcenter.

Having described my invention, what I claim, and desire to secure byLetters Patent, is as follows:

1. In a treadle mechanism, a rock shaft supported at one end. in aswiveled hearing attachedto the engine or other machine operated by thetreadle, and at the other end in a movable stand or support, andprovided with cranks, to which the treadle proper or footpiece and thepitman are respectively connected, snbstantiall; as set forth.

2. The cranked and flexible or jointed rockshaft, in combination withthe movable stand or treadle-support and the treadle, substantially asshown and described.

3. The cranked and flexible or jointed rockshaft and its swiveledbearing, in combination with the movable stand or treadle-support andthe treadle, as set forth.

4. The combination, with, the rock-shaft and the movable stand ortreadle-support, of the treadle or foot-piece, united with the outercrank on said shaft bya swiveled connecting- ALONZO H. STEVENS.

Witnesses:

ALFRED HULL, JOHN A; STANTON.

